The number of holes in the grinder plate will vary by the diameter of the plate, so basically the larger the plate the more holes the plate can have. Example: 3/4" plate for a #10/12 grinder may have 5 holes while a #22 grinder plate may have 6 holes. The first meat grinder was invented in the nineteenth century by Karl Drais. The earliest form of the meat grinder was hand-cranked and forced meat into a metal plate that had several small holes, resulting in long, thin strands of meat. This LEM clamp-on hand grinder is a sturdy device, which could last you many years. It will pretty much chew up any cut of pork, beef, or game that you can throw at it. The stainless steel will ensure it doesn't rust, with parts that don't contain any harmful chemicals to alter the taste or quality of the food. Use a brush to clean the rusty part: You can pass some fatty red meat through the grinder to take out rust. After each use, apply vegetable oil lightly to the iron parts to prevent them from rusting. Ensure that the oil soaks them well, and then clean it off before the next use.